CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock Par Value [Member]	Capital in Excess of Par Value [Member]	Retained Earnings/(Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income (Loss) ("AOCI") [Member]	Treasury Stock [Member]	Stockholder's Equity [Member]	Noncontrolling Interest ("NCI") [Member]
Beginning Balance at Dec. 31, 2015					$ (93,955)
Net income	$ 19,361
Other comprehensive income (loss), net of tax	28,059				28,080
Ending Balance at Jun. 30, 2016					(65,875)
Beginning Balance at Mar. 31, 2016					(66,489)
Net income	21,805
Other comprehensive income (loss), net of tax	606				614
Ending Balance at Jun. 30, 2016					(65,875)
Beginning Balance at Dec. 31, 2016	1,595,468	$ 249,690	$ 1,695,119	$ (226,767)	(66,895)	$ (94,957)	$ 1,556,190	$ 39,278
Net income	60,654			58,329			58,329	2,325
Other comprehensive income (loss), net of tax	10,686				10,704		10,704	(18)
Common stock issued		43,584	(43,584)
Stock-based compensation charges	8,519		8,519				8,519
Purchase of treasury shares	(7,020)					(7,020)	(7,020)
Retirement of common stock		(805)	(4,928)			5,733
Acquisition of NCI	(6,775)		2,121		2,284		2,121	(8,896)
Other	(1,036)		(1,016)				(1,016)	(20)
Ending Balance at Jun. 30, 2017	1,660,496	292,469	1,656,231	(168,438)	(56,191)	(96,244)	1,627,827	32,669
Net income	36,459
Other comprehensive income (loss), net of tax	8,293				8,293
Acquisition of NCI					2,284
Ending Balance at Jun. 30, 2017	$ 1,660,496	$ 292,469	$ 1,656,231	$ (168,438)	$ (56,191)	$ (96,244)	$ 1,627,827	$ 32,669